Best engine oil for mk1 golf GTI

Hello everyone,

I have a 1982 Mk1 golf GTI campaign. The engine had been restored by BR motorsport in 1999 with the 152bhp conversion, then had the K-star ECU fitted. I am about to service the car, what is the best oil for my engine? Or will any decent make 10W 40 Semi-Synthetic do?

I have been meaning to ask this as well. I've had 20W-50 recommended to me, but am wondering if that will be too thick.

Also after advice on whether to get full mineral, or semi-synthetic as suggested above.

I can easily get Royal Purple 20W-50 for about AU$90 (£50) a 5L bottle, or do I just go with a Castrol/Shell/whatever for about AU$30 (£15-20) per bottle?

Someone must know on here?

I have had no problem with 10w 40 but after abit of research (courtesy of the Castrol website) they recommend 5w 30 Castrol Edge which is going in for my next change due soon!

Slade said

I have had no problem with 10w 40 but after abit of research (courtesy of the Castrol website) they recommend 5w 30 Castrol Edge which is going in for my next change due soon!

I think if I were manufacturing oil, I'd recommend the one I sell too.

10W40 semi synth is fine. So is 15W40 mineral oil.  And 5W40 or 0W40, or fully synthetic if you like, but you'll see no additional benefit in exceeding the winter viscosity, or quality rating, which is SH for this era engine. Modern oils are typically SL these days, so greatly exceed the quality spec.

Even Asda 10W/40 semi synth is going to be okay in the engine.

These days I just buy on price.

I've noticed that my engine burns less oil with castrol 15/40.

15/40 is what I always use and have always used

I always use Quantum Synta 10/40 semi synthetic with no problems. Interested to read engine uses / burns less oil with 15/40 my try this in the wifes 2.0 ltr New Beetle which has an appetite for the stuff

if you look on the back of the castrol gtx 15/40, it says for older and worn engines.

i always thought 15/40 was one of the thicker oils

golf1 said

if you look on the back of the castrol gtx 15/40, it says for older and worn engines.

i always thought 15/40 was one of the thicker oils

It is.. its thicker so that it doesnt squeeze past the pistons and stem seals at higher running temps.

Madferret said

golf1 said

if you look on the back of the castrol gtx 15/40, it says for older and worn engines.

i always thought 15/40 was one of the thicker oils

It is.. its thicker so that it doesnt squeeze past the pistons and stem seals at higher running temps.

Not true.  The difference between a 10/40 and 15/40 oil is the cold temp viscosity (10 is thinnner when cold, 15 is thicker when cold).  Both have the same hot temperature viscosity/thickness - the 40 bit.

Asim said

Madferret said

golf1 said

if you look on the back of the castrol gtx 15/40, it says for older and worn engines.

i always thought 15/40 was one of the thicker oils

It is.. its thicker so that it doesnt squeeze past the pistons and stem seals at higher running temps.

Not true.  The difference between a 10/40 and 15/40 oil is the cold temp viscosity (10 is thinnner when cold, 15 is thicker when cold).  Both have the same hot temperature viscosity/thickness - the 40 bit.

I wasnt comparing it with 10/40

15w40 was mostly older diesels and worn petrols,go synta or similar 10w40,i ude it in my TD and cabby and citigolf,always have good oil pressure too,the secret is a quality filter ie mahle,bosch,genuine etc  :wink:
Bert

Madferret said

Asim said

Madferret said

golf1 said

if you look on the back of the castrol gtx 15/40, it says for older and worn engines.

i always thought 15/40 was one of the thicker oils

It is.. its thicker so that it doesnt squeeze past the pistons and stem seals at higher running temps.

Not true.  The difference between a 10/40 and 15/40 oil is the cold temp viscosity (10 is thinnner when cold, 15 is thicker when cold).  Both have the same hot temperature viscosity/thickness - the 40 bit.

I wasnt comparing it with 10/40

Ok, what were you comparing it to?  You wrote this:

It is.. its thicker so that it doesnt squeeze past the pistons and stem seals at higher running temps.

does golden syrup in the oil reduce blue smoke then?

He said I thought it was one of the thicker oils, so I said "It is".  :roll:

I run 5/30 on mine.

Come across this on google which was quite useful:

The first number denotes how the oil flows at a cold temperature. Lower the number, the easier it flows when cold. Second number (after the W) denotes how the oil flows when hot (operating temperature). Larger the number, the better for some cases.

Most new cars are designed to run 5W30 year-round in most climates. The proper weight for your car depends on year of car, mileage on car, and how cold or hot it's gonna be outside when you start it.

Guess with the lovely weather in the UK, we can get away with 5/20